Lift jack



T. M. PARKER Dec. 26, 1950 LIFT JACK 2 Sheets-Sheet 1 Filed June 3, 1948 ZMlDa'er T. M. PARKER Dec. 26, 1950 LIFT JACK Y 2 Sheets-Sheet 2 Filed June I5, .1948

3mm re 7" YM i Patented Dec. 26, 1950 UNITED STATES PATENT OFFICE LIFT JACK Ted M.`Parker, Kansas City, Mo.

Application ,l une 3, 1948, Serial No. `30,825

3 Claims. I

My invention relates to -a lift jack and more particularly to a hand lift jack that is portable and adapted to employ a suitable means, such as a screw or hydraulic jack, for raising and lowering the lift arm or boom thereof for lifting loads such as motors or other objects as in a garage, Shop or manufacturing plant, one end of an automobile or the like, and depending upon the size and capacity thereof, up to 2500 pounds or more.

An object is to provide a portable lift jack having a frame with a base supported on wheels, inn cluding steering wheels on a turn table or fifth wheel with a handle to pull or push it around from place to place where it is to be used so as to be properly and accurately positioned relative tc the load or object to be lifted.

Another object is to provide a lift jack having a wheeled carriage, frame or base with an upright member or mast thereon at one end, preferably the steering end, and an overhanging arm or boom hinged or pivoted to the top of the frame and so correlated thereto as to extend over the frame or base to engage an object to be lifted, this arrangement precluding the possibility of the jack tipping over and means, such as a hydraulic or screw jack between the frame and vertically movable or swingable lifting arm or boom to raise or lower the latter and thus an object connected to or arranged above or beneath the arm or boom.

Another object is to so construct the lifting arm or boom that same is permanent `while the length thereof may be extended, an extension boom, arm, part or element being provided for this purpose having means correlative with the boom to detachably fix the extension element to the arm so that it will be rigid therewith when used or readily detached or removed from the permanent lifting arm or boom whereby the latter or shorter normal length may be used as dictated by the lifting job at hand.

To the foregoing objects, and others which may hereinafter more fully appear, the invention consists of the novel construction, combination and arrangement of parts, as will be more specifically referred to and illustrated in the accompanying drawings, but it is to be understood that changes, variations, and modifications may be resorted to which fall within the scope of the invention as claimed.

In the drawings,

Figure 1 is a top plan View of a lifting jack embodying my invention,

Figure 2 is a side view of the lifting jack,

Figure 3 is an end View thereof,

Figure 4 is an enlarged detailed fragmentary vertical sectional view showing the mounting of the turn table or fifth `wheel for steering the portable wheeled frame or base of the lifting jack,

Figure 5 is a fragmentary detail `plan View showing the extension boom lassociated in correlative position to the lifting arm or boom for use as in Figure 2.

Referring to the drawings, the lift jack embodies a substantially `horizontal wheeled carriage, frame `or base I9 of substantially `U--shape having sides l'-I a transverse closed front end or bight portion and the opposite or rear end open and the rear ends of sides II provided with `bearing forks I2. The frame may be constructed of suitable `bar metal such `as flat stock, angle iron, `or otherwise and `the `sides II are connected at points spaced from the open rear end and forks I2, as through the medium of an inverted angle `bar i3 welded or otherwise attached at its ends to said sides. The extremities of the sides or legs I I are provided with upwardly converging side plates M, all parts where connected being welded or otherwise `fastened together. The upper ends of the side membersV or plates I4 have portions I 5 substantially parallel to each other and provided with holes to receive a horizontal shaft or transverse pivot IS `which may be solid or a pipe. The sides il at the bottom portions of the side members or plates I4 are also connected by a #transverse bar I'I which may `be `in the form of a channel as shown, or otherwise, so as to effectively brace the frame at this end and preferably adjacent the top edges of the side members II.

The `members, I4 form a mast and pivoted to `the shaft IS, at one end, is a vertically swinging arm or `boom I8 having converging sides I9 forming an isosceles triangle centered over the fth wheel 4I with the apex thereof extending toward the front of the frame I0 with apertured parallel end portions 20 receiving the shaft in connection with the upper end portions I5 ofthe side members I4, the shaft being held by suit,- able retaining means on its ends indicated as Cotter pins 2I. Also, the portions 20 are preferably disposed in Contact with the inner sides of the portions I5 and converge toward their `free ends and the free end of the arm or boom I8 Where they are secured .together as at 22, `by Welding or otherwise. Near their free ends, the sides I9 are in Vcontact and provided `with `top recesses `23 forming a hook over which a chain or other element may be disposed for raising and supporting a load, A cross brace 24 connects the 3 converging sides I9 near the pivot end of the arm or boom.

The base is' further strengthened by angular reinforcing or gusset plates welded along the top edges of the sides I I and the lower portions of the front edges of the side members or plates I4 of the mast, the sides I4 preferably sloping beyond the adjacent end of the base as indicated, particularly in Figure 2 of the drawings, and the adjacent end portions of the reinforcing plates,

Webs or gussets 25 being similarly inclined and tapered as shown so as to somewhat conform to the inclined edges of the sides I4. In addition, oppositely inclined or diagonal braces 26 are extended between the sides I4 and the cross brace I'I and at their upper ends, support a horizontal plate or table 2l which is connected at its ends to the sides I4 at an elevated point, as by welding and has a forwardly extending tapered portion on which a transverse tubular member or pipe 28 is arranged to support a plate 29 having an angle iron rim 30 Within Which a screw or hydraulic jack 3I is mounted. The jack is adapted to be operated by a crank 32 and has movable plunger 33 and a head 34 with a transverse tubular or pipe bearing member 35 to engage beneath the cross brace or plate 24 whereby upon operating the hand jack, the arm or boom I 8 may be raised or lowered to raise or lower a load attached to the free end of the free end thereof.

At the open rear end, the forks I2 of the frame are each provided with a short transverse axle 36 shown as located outwardly of sides I I of the jack frame or truck I0 with bars attached at the outside of bars II to form the forks I2 therewith, f

and the axles 36 held in bearing boxes 3l to take wheels 33 so that the jack frame or truck can straddle a load or be backed up to a bench to set the load down conveniently or with no trouble. Wheels 33 are shown as having suitable antifriction bearings 39, if desired, and axles 36 are held in position as by suitable retaining means such as cotter pins 4t. At the opposite end, the cross brace or channel Il bears on a turn table or fth wheel 4I comprising longitudinal parallel short bars 42 disposed on edge and parallel to each other and also welded equidistantly on either side of the center of length of the cross brace I'I at the bottom thereof. A disc or circular plate 43 is secured to the bars 42 and bears on a sirnilar disc or plate 44, While a kingpin or center pivot 45 extends centrally through the discs and an axle 45 at this narrow end of the frame, which as shown is preferably formed of an inverted channel-shaped member of considerably shorter length than the frame but provided with reduced spindle ends il to take wheels 43 constituting the steering wheels of the device and equipped, if desired, with similar bearings 39 and held in position by cotter pins 4Q the Same as described in vconnection with the rear axles and wheels. lIhese wheels 48 are positioned at a spaced distance inwardly from the sides of the frame as clearly shown in Figure 3 of the drawings and the outer edge of the axle is -provided with apertured pivot ears or lugs 49 to which a fork 50 at the inner end of a handle bar 5I is pivoted horizontally to swing up and down as indicated at 52. The fork 5@ comprises bars of metal anchored on each side of the handle bar 5I at parallel portions 53 by welding or otherwise at their converging ends and the free end of the handle bar is provided with a cross bar or handle 54.

Means is provided for extending the length of the arm or boom I8 and for this purpose, an extension arm or boom 55 is provided, this part or element comprising spaced bars 56 bent toward each other at common ends as indicated at 51 and Welded or otherwise anchored together as indicated at 58 and formed with recesses 59 in their top edges to provide a hook similar to the end of the arm I8. The spaced portions 56 are connected by a lower cross member or bolt 60 near their inner ends and lower edges and by a similar bolt 6I spaced therefrom near their top edges, so that the extension part or element may be slipped over the free end of the arm I8 with the bolt 60 extending under the ends 22 and the bolt BI seating in the recess 23 to hold the extension arm or boom rigid to give greater length and leverage.

It will thus be seen that I have provided portable, hand lift jack in which the vertically swingable arm or boom extends over the wheeled frame cr base from one end and in this way will support the load to be raised or lowered without tipping over. This is also facilitated and the extension of the base from the mast and the boom or arm tliereover increased, to enlarge the distance that thedevice may be projected over an object to be raised by having the boom or arm pivoted over one end of the base or wheeled frame and also because of the rearwardly inclined or sloping position of the mast relative thereto. For instance, the wheeled base or frame may be extended beneath an automobile and the arm or boom projected into a car or over a motor to lift the transmission or motor as it is thought will be obvious. Other large loads may be correspondingly liited by operation of the jack disposed in spaced relation but adjacent to the pivoted end of the arm or boom, so as to make the device especially useful in a garage, shop or manufacturing plant ior lifting various loads. Also, by reason of the handle and turn table at one end of the wheeled frame or base and the steering wheels pivoted as described, the steering of the device is facilitated and the jack may be accurately and properly positioned relative to the load in addition to being conveniently pulled or pushed around from place to place Iwhere it is to be used.

I claim:

l. A portable lift jack comprising a wheeled base frame having axles and wheels including steering Wheels at one end of the frame, a handle bar connected to the steering wheel axle, said latter axle having a fifth wheel connection to the frame, a mast including side bars attached to the frame at points disposed outwardly of and to each side of said fth wheel sloping inwardly and up- Wardly With ends thereof terminating beyond the end cf the frame to form fixed spaced ends disposed above and rearwardly of said fifth wheel, an arm having spaced sides pivoted to the upper ends of the side bars of the mast for vertical swinging movement and overhanging the frame, and a horizontal support carried by the mast having side bars formed with divergent ends secured to the frame.

2. A portable lift jack comprising a wheeled base frame having axles and wheels including steering lwheels at one end of the frame, a handle bar connected to the steering wheel axle, said latter axle having a iifth wheel connection to the frame, a mast including side bars supported by the frame and having sloping upper ends extended beyond the end or the frame, an arm having sides pivoted to the upper ends of the side bars of the mast for vertical swinging movement and overhanging the frame, a horizontal support disposed under said arm having divergent vertical side bars carried by the frame, the sides of the arm being spaced and secured in contact toward their free ends and having a top recess Vformed transversely thereof, and lift means pivotally carried by and having a movable head engageable with the support and bottom of the arm to raise the latter.

3. A Wheeled hoist comprising a base frame having a pair of spaced side members joined at ends thereof by a cross member to form a closed i rear end portion with opposite ends of said side members being extended to form a pair of free ends spaced from said cross member forming an open front end, spur shafts extending outwardly of said front end at right angles thereto, wheel means mounted on said spur shafts, a fth wheel mount carried by said cross member at the rear end of the frame with spaced wheels carried by said mount movable about the axis thereof for steering, a mast carried by said frame having spaced side plates extending upwardhI and rearwardly from each of said side members of the frame with terminating ends thereof spaced apart above and to the rear of said base frame, a transverse bar extending between said terminating ends, a lift boom formed with a pair of converg ing side members pivotaliy mounted on said transverse bar with the convergingr ends thereof extended and joined together for vertical movement above the front end of said frame, the spaced portion of said boom members forming an isosceles triangle disposed above said ith wheel, a support carried by said mast having spaced uprights extending from said side members, and pivoted lift means carried by said support disposed under said boom.

TED M. PARKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,837,965 Stoner Nov. 15, 1932 2,208,221 McCullough July 16, 1940 2,335,130 Moran Nov. 23, 1943 2,387,744 Clapp Oct.. 30, 1945 2,389,873 Ruger Nov'. 27, 1945 FOREIGN PATENTS Number Country Date 653,079 Germany Nov. 13, 1937 792,480 France Dec. 31, 1935 

